I just upgraded my Samsung tab to Android 12, and decided to test Apps2SD again. Unfortunately my results are the same as before. You can link an app's internal data just fine, linked apps continue working. However, linking obb files to 2nd partition fails. I can link them to the SD's 1st partition, Apps2SD claims linking is successful. But when I check the /Android/obb/ folder on SD, nothing has been moved, and the respective app fails to launch normally.
In short, for Android 11/12, you shouldn't trust Apps2SD to link anything in /sdcard/Android/data or /sdcard/Android/obb, due to the Scoped Storage restrictions. The locations listed above may also/or be located at /storage/emulated/0 on some firmwares. However, linking an app's internal data (located in the data partition, not including internal/external storage) seems to be safe. It's a long shot that Apps2SD will ever be updated, but we can hope.
Most Apps2SD users will be rooted with Magisk these days, so be sure to use /data/adb/service.d for the mount script location (configure it in Apps2SD settings before creating mount script). Also, it's best to not let Apps2SD modify system partition. Using the advanced mount option will likely result in a failure to create the script, or an inability to boot.
Here are some alternatives you can try to address these shortcomings:
XInternalSD:
Requires EdXposed or LSPosed
Can't link internal data
Can select which apps it should be enabled/disabled for
Doesn't require 2nd partition on SD
Obb On SD:
Requires EdXposed or LSPosed
Can't link internal data
Can't select which apps to enable it for
The app will claim it's not enabled in Xposed, you can just ignore this by tapping outside the dialog, it will still work
Doesn't require 2nd partition on SD
Fbind:
Requires Magisk/root
Can't link internal data
Requires usage of a terminal emulator app, it has no GUI
Doesn't require 2nd partition on SD
Not all of these will work with all apps, try more than one if you have issues.
Even with these issues, I think that Apps2SD still remains somewhat useful, but not as much as it was before on older Android versions. If you're willing to root your phone and try EdXposed/LSPosed, you will find that these limitations are tolerable.
An alternative for non rooted users would be adoptable storage.